Maxillodental measuring instrument



Dec.. 13,, 1949 ,1. A. SALZMANN 2,491,136

MAXILLO-DENTAL MEASURING INSTRUMENT Fil ed Oct. 6, 1945 s s eets-sheet 1 INVENTOR. @0029 J? Salgmann Dec. 13, 1949 J. A. SALZMANN 2,491,136

MAXILLO-DENTAL MEASURING INSTRUMENT Filed Oct. 6, 1945 3 Sheets-Sheet 2 1 ii i i3 mmvrok. ficob .77. 3912 7711 171.

Dec. 13, 1949 J. A. SALZMANN 2,491,136

1 MAXILLO-DENTAL MEASURING INSTRUMENT Filed Oct. 6, 1945 1 s sheets-sheet s FiqE INVENTOR. Jaoab'fl SaZ ma'n/n/ Patented Dec. 13, 1949 PATENT OFFICE amuse- INSTRUMENT Jacob A;-Salzmann, Forest-Kills;- Application iicfdbef 631945; serial-No. 626m 4 Glaims:

The present inventiofi rela'tes to a mjaxillo'd'ehtal' measuring instrument and-more] particularly; to' a device for taking firecisemaziillodeiital and; to a more limited ezitefit', maxillofaeial" measure: ments. to'measure anatomical features and relationships in' orthodontia, dental prosthesis arid m'a'xilldfacial prosthesis. This device" renders it uh necessary to employ casts" of the face and jaws; X-ray's; photographs", facial tracings; head Desi-'- tiohing apparatus and other time consuming methods andcostly equipment-"now employed in taking measurements the field's above men; tioned, as well as" in such other fields as plastic surgery, physical anthropology; comparative dental anatom'y'and statisticalstudies of the growth; development and change of the face and jaws; The deviceher'eiri' claimed may also be used for obtaining" data useful in identification of faces"; skulls and their component parts. p

The principal object of the inveiitioii; there:

fore, is the provision of a measuring instrument" of the character described by'whicli' all O f tl'ie measurements hereinabbve referred to may be takeri with great ease and accuracy.-

Another object of the ihv'e'htibli i's' tli provision' how the device is used in connection witha face"- having mandibular protraction; and

Fig-.- 6 is a" similar view showing the use'of the' device on' a face having maxillary p'rotraetion and mandibular retraction.

Referring now to the drawing and, more particularly, to-Figs. 1-- and-2 thereof,itwil1'be seen that the device herein claimed comprises" the following elements: A graduated square l having:

anaperture: H at a point adjacent the apex thereof midway between the twosides tliereiif and also having a horizontal-slot l'2 and a'vertical slot l3 whose axes intersect,- respect'ively the axis of the aperture H, an ind'icator I4 mountedin the a erture Fl ,t a Siibhd iridiatof' [5"51163513?" The device herein claimed may be used a fourth indicator ll also slidably mounted in slot I3" below indicator I6, a protractor [8 sea: 5

at" the free end of'radial a-r'm [9, a fifth indicator 2| mounted centrally of said secondprotractor a second radial arm 22 provided with a slot 24 by which it is mounted on; the fi'ft liindicator 2| centrally of the second protractor 26 for pivotal and slidable movement relative to said second pro tractorand a third radial arm '23 mounted on said fourth indicator ll.

15 It will be noted that the square l9 whichtak'es the preferred formof a right angle triangle, is

graduated on its horizontal and vertical sides. The metric system has been followed in the pre'-' ferred embodiment and" has been found to be ms eminently suitable for the purposes indicated.

The indicators M, I5, [6, l? and 2! above referred to are all of substantially the same con struction' and each comprises the following component parts: A screw 30 having areduc'ed end 3|", a quicli adjusting wing clamp 32, a' nut 33 and a pair of washers 3% between said clamp and said nut; Washers 34 are'dispo sed one on each side of square I; In th'e'case of the indicator M;- the screw is carried within the aperture H; In the case of the indicator 15, the screw 3i] is slidably mounted inhdrizontal' slot l2. In the case of indicators It and H, the screws 36 are slidaloly mounted in vertical slot IS' and in the case of indicator 2 l, the screw 36 is mounted M a 1 hole in the center of the protractor 29.

It will-be noted in' Fig. 2 that a fin 40 of substantially triangular shape is afiixed to the side ofthe radial arm I9; said fin extending substantially across the major part of the protractor l8; Theobject of this finwill shortly become apparent; It'is'sufficien't, however, to say here that the second radialarnij22 is provided with a cor responding fin" H which is affixed tothe side of saidsecond radialarni' on a'plane which is'int'ersected by the plane of fin 40 at right angles.

Thethird'radial arm'23coiiinri'ses the following component parts: arm 58 which is pivotally mc'iiiii'ted on the screw 33 of the indicator H, an L-shaped member 5| which is telescopically enag'd at'oh'e of its ends with said arm 50 and which is telescopically engaged at its other end with a second L-shaped member 5 2. In the preferred embodiment of this invention, the L-shaped member Eli's a hollow tube having a curves: aria-aha side; and am an are second trally mounted on indicator H,- a' radial arni- [9' affixed tosaid protractor a second protracto'r 20 L-shaped member 52 constitute half-round wires whose dimensions and shape correspond to the inner dimensions and shape of the tubular L-shaped member 5|. It will be understood that members 50 and 52 are adapted to engage in axial movement only with respect to said tubular L-shaped member 5|. The entire assembly, to wit, members 50, 5| and 52 which together constitute the third radial arm 23, is movable pivotally with respect to the screw 30 of the indicator ll.

Upon consideration of the foregoing, it will be understood that when the device is held in the position shown in Fig. 1, the indicators l4 and I5 may be used to measure horizontal distances and the indicators [4 and [6 or M and I! may be used to measure vertical distances. The first radial arm I9 is pivotally mounted with respect to the vertical side and slot of the square I0. Since the vertical side and slot are in fixed relationship with the horizontal side and slot, there will be a definite correspondence between the angle formed between the radial arm l9 and the vertical slot and side, and the angle formed between the radial arm I!) and the horizontal slot and side. Such being the case, the protractor l8 to which said radial arm I9 is affixed will measure not only the angle between said radial arm and the vertical slot and side but also the angle between said radial arm and the horizontal slot and side. It will also be understood from the foregoing that the protractor 20 will measure the angle between the second radial arm 22 and the first radial arm l9 and that a definite geometrical relationship may be set up at any particular time between the longitudinal axis of the second radial arm 22 and the horizontal slot and side or between said longitudinal axis of the radial arm 22 and the vertical slot and side.

The device hereinabove described may be used as follows, reference being made especially to Figs. 3 and 6, inclusive: To measure the length of the Frankfort plane on a straight line, the indicator I4 is placed at the orbital point and the indicator l5 at the tragion point. The latter indicator I5 is now clamped to the square l and a reading taken on the horizontal side of said square. To measure the length of the face on a straight line from the orbital point to the lower edge of the mandible, the indicator I4 is placed at the orbital point and the indicator I6 or the indicator I1 is placed at a point opposite the lower edge of the mandible. A reading is now taken on the vertical side of the square H). To ascertain the mesiodistal relation of the maxillary dental arch to the orbital plane, place the indicator i l at the orbital point, indicator l at the tragion point and indicator H5 at the incisal edge of the maxillary tooth which lies opposite indicator l6. To ascertain the relationship of the mandibular teeth to the orbital plane, follow the procedure last above described but place the indicator IE5 or the indicator IT at the The fin 40 thus describes the mandibular base plane, i. e. the plane tangent to the must dependent points of the lower border of the mandible. The size of the Frankfort mandibular base angle which is the angle formed between the Frankfort plane and the mandibular base plane is thus shown on the protractor l8.

With particular reference to Fig. 5 the adjustment is made by holding the square against the face with the left hand. Screw I4 is adjusted at the infra-orbital point and screw I5 is adjusted at the tragion point. Radial arm I9 is placed under the base of the jaw and adjacent to the lower border of the mandible. The reading of the angle between the Frankfort plane which is measured from the infra-orbital point to the tragion point as indicated above and the line tangent to the base of the jaw is then read on protractor l8.

Fig. 6 shows the second radial arm 22 measuring the Gonion angle formed by a line tangent to the vertical extension of the jaw or ramus and the base of the mandible. The reading is taken on protractor 20.

To obtain the Gonion angle, the fin 4| of the second radial arm 22 is placed in back of the ramus and said fin thereby becomes what may here be known as the ramus piece, and the fin 4B which may herein be known as the mandibular base piece is placed against the lower border of the mandible as described above. A reading on the protractor 20 Will now give the Gonion angle.

To obtain the incisor-mandibular plane angle, place the mandibular base piece or fin 40 against the base of the mandible as above described. Adjust the third radial arm 23 so that the free end of the L-shaped wire 52 lies against the lingual surface of the mandibular central incisor, right or left, whichever is more typical of the inclination of the other mandibular incisors. A reading of the protractor I8, the radial member 50 serving as the indicating arm with respect thereto, will give the incisor-mandibular plane angle.

It will be understood that what has been above described is but a preferred embodiment of the invention. Different types of indicating members and clamping means may be used in place of those shown in the drawing and herein described. The material of which the different parts are made may be varied to suit different purposes and conditions. It has been found, for example, that the plastic material sold under the trade mark Plexiglas is a highly desirable material from which the square, protractors and radial arms I9 and 22 may be made. It will be understood, too, that the device herein described may be mounted on a stand for greater ease in applying and using the same or conventional head clamps may be used to hold the device in place. When using a conventional head clamp, two devices may simultaneously be usedone on each side of the face. To render the device even more precise, a pair of vertical and horizontal levels 60 and 6|, respectively, may be mounted on the square l0 and a similar pair of levels 62 and 63 may be mounted on the fin or mandibular base piece 40.

I claim:

1. A maxillodental measuring device comprising a graduated square, indicators on said square movable parallel to the sides thereof for measuring linear distances on lines which are perpendicular to each other, a protractor on said square movable parallel to one of the sides thereof, a radial arm fixed to said protractor and a second radial arm pivoted to said protractor, the angle between the two arms and the angle between said arms and the sides of the square being measurable by said protractor, said first arm being provided at its free end with a second protractor and a third radial arm pivotally and slidably mounted with respect to said first arm, the angle between said first and third arms being measurable by said second protractor, said first radial arm being provided with a substantially triangular fin afiixed at right angles thereto, said fin being adapted for positioning along the base of the mandible.

2. A maxiliodental measuring device comprising a graduated square, indicators on said square movable parallel to the sides thereof for measuring linear distances on lines which are perpendicular to each other, a protractor on said square movable parallel to one of the sides thereof, a radial arm fixed to said protractor and a second radial arm pivoted to said protractor, the angle between the two arms and the angle between said arms and the sides of the square being measurable by said protractor, said first arm being provided at its free end with a second protractor and a third radial arm pivotally and slidably mounted with respect to said first arm, the angle between said first and third arms being measurable by said second protractor, said third radial arm being provided with a substantially triangular fin afiixed at right angles thereto, said fin being adapted for positioning along the ramus.

3. A maxilla-dental measuring device comprising a graduated square, indicators movable parallel to the horizontal side of said square, one ofsaid indicators being adjustable at the infraorbital point on the human face and the second of said indicators being adjustable at the tragion point, an indicator movable parallel to the vertical side of said square, said latter indicator being adjustable at the base of the mandible, an arm pivoted at one end to the lower end of the vertical side of the square, a protractor for measuring the angle between the vertical side of the square and said arm, said arm being positionable along the base of the mandible, a second arm being pivotally and slidably mounted at the free end of the first arm and being positionable along the ramus, a protractor for determining the angle between said first and second arms, a third arm pivotally mounted on a common axis with the pivot of the first arm, said third arm being positioned to engage the lingual surface of the mandibular central incisor, and a protractor for determining the angle between said first and third arms.

4. A measuring device in accordance with claim 3 in which the indicators and the arms are provided with horizontally extending projections which are substantially perpendicular to the side of the square and to the sides of said arms, said projections being of a length sufiicient to reach those parts of the face which lie opposite them.

JACOB A. SALZMANN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,050,969 McLeod Jan. 21, 1913 1,378,745 Wavrin May 17, 1921 1,661,096 Rowe Feb. 28, 1928 2,043,230 Boll et al June 9, 1936 2,095,059 Donnelly Oct. 5, 1937 FOREIGN PATENTS Number Country Date 9,585 Great Britain A. D. 1896 427,610 Germany Apr. 16, 1926 657,389 Germany Mar. 3, 1938 

